In the early 1980s I volunteered to work in Killarney National Park in Ireland on a project to rid the oak woodlands of Rhododendron ponticum, an invasive shrub that was encroaching in the understory of this habitat. The concern was that this invasive species prevented the regeneration of oak. Since oak woodland, or in fact any woodland type other than spruce plantation, is rare in Ireland, Rhododondron, that most beautiful of vandals, could wreck a national treasure. Many of the volunteers were, like me, students from one of the colleges in the National University of Ireland system. We stayed in a deconsecrated church at the edge of the park and would travel by boat across the delightful Lakes of Killarney to our worksite for the day. At the foot of the mountainous slopes upon which these woodlands are found, the ground is boggy. These small patches of bog are themselves of some interest botanically – often dominated by heather and gorse, with an occasional butterwort (a carnivorous species). Some of these bogs were so spongy underfoot that if one hopped up and down a little (ah youth!) the entire landscape would respond – slowly at first, and then like a slow green sea the ground would sinuate out towards the woody margins where the trees themselves would seem to sway.